Aero-refrigeration tower with passage for bypassing a humidification device in a mixed module of the tower

ABSTRACT

An air-cooling tower comprising an air intake unit, a dry unit and a mixed unit between the intake unit and the dry unit, with the units being adjacent, with the intake unit being configured to draw outside air and transfer it to the mixed unit, at least one passage of humidification of discharged air passing through at least one humidification device of the mixed unit. At least one passage as a by-pass separate from said at least one passage of humidification passes through the mixed unit outside of the space occupied by the at least one humidification device and connecting the air intake unit to the dry unit, the at least one passage as a by-pass being partitioned with respect to the at least one passage of humidification and to the at least one humidification device.

TECHNICAL FIELD OF THE INVENTION

The invention relates to the field of air-cooling towers.

More particularly, the invention relates to a hybrid air-cooling tower comprising an air intake unit in the form of a ventilation unit, a mixed unit and a dry unit.

According to a first embodiment, referred to as “blower fan”, the mixed unit is adjacent to the ventilation unit and the dry unit is adjacent to the wet unit, with the ventilation unit drawing outside air and discharging it to the wet unit, at least one passage of humidification of discharged air passing through a humidification device of the wet unit.

The units are preferably superimposed by forming a vertical air-cooling tower.

According to a second embodiment, referred to as “drawing fan(s)”, the hybrid air-cooling tower comprises a unit for introducing air adjacent to the mixed unit and a mixed unit adjacent to a dry unit, and a dry unit adjacent to an upper ventilation unit. There is therefore, according to a vertical direction, an air inlet intake unit comprising air inlet grids, adjacent to the mixed unit, a mixed unit adjacent to the dry unit.

PRIOR ART

Such a hybrid air-cooling tower is known from prior art. A ventilation unit is associated with one or several centrifugal fans or fan-motor assemblies which are arranged exteriorly to the unit, with this or these fans being referred to as centrifugal fans. The ventilation unit can also be associated with a helical fan.

The wet unit comprises at least one humidification device or we tower exchanger for evaporative cooling. This humidification device is frequently in the form of a sprayed battery with smooth tubes with at least one spraying device directly in line with the battery. Said at least one humidification device is supplemented by a drop separator. In such a humidification device the pressure loss on the air at 3.5 m/sec is about 400 Pa.

The dry unit comprises a dry battery i.e. without spraying of water. This battery has to correspond to the dimensions of said at least one humidification device in order to be superimposed on the humidification device by being placed at a distance from the latter. It then follows that the dry battery of the dry unit is under-sized in order to correspond to the humidification device. For such a dry battery, the pressure loss on the air at 3.5 m/sec is about 250 Pa.

Such an air-cooling tower can operate according to two main modes namely a dry mode for which the dry unit carries out the cooling and a wet mode for which said at least one humidification device provides the cooling.

Such an air-cooling tower has disadvantages.

One of the disadvantages is the required under-sizing of the dry battery in order to adapt it to the dimension with said at least one humidification device although it could be considered to use a larger dry battery, if all of the air did not pass through said at least one humidification device prior to its passage in the dry battery. The front surface would be sized for an air speed of less than 2.5 m/second instead of 3.5 m/second corresponding to the speed of the humidification device, which is a minimum gain of 30% on the surface and a decrease in pressure losses on the air of: 50%.

Another disadvantage is the accumulation of pressure losses on the air in the wet unit and the dry unit. Even in dry mode, all of the air flow passes through the humidification device. Indeed, regardless of the operating mode, wet and dry batteries are used and are passed through by the air. The aforementioned pressure losses of about 400 and 250 Pa are added together to give a pressure loss of about 650-700 Pa.

A dry battery provides all of its capacity with a speed of the passage of the air of 2.5 m/s and a pressure loss of about 125 Pa. However, the humidification device gives all of its capacity with a speed of 3.5 m/s and a pressure loss of about 400 Pa.

This is particularly disadvantageous for an operation of the air-cooling tower in dry mode. This mode is the most common for the use of the air-cooling tower and it can be evaluated that it is active 8 or 10 months per year. In an air-cooling tower for such a dry mode for which it is not necessary to humidify the air, all of the air is however forced to pass through said at least one humidification device. Even when said at least one humidification device is not activated, the pressure loss incurred is not negligible.

An object of this invention is therefore to propose an air-cooling tower that can have reduced pressure losses by not forcing in a required manner at least one portion of the air to pass through said at least one humidification device of the wet unit, this primarily for a dry mode of operation of the air-cooling tower or a mode other than the wet mode.

SUMMARY OF THE INVENTION

To this effect, this invention relates to a hybrid air-cooling tower comprising an air intake unit, a dry unit and at least one humidification device, the dry unit being adjacent to the humidification device, the air intake unit being configured to draw outside air and transfer it to the humidification device, at least one passage of humidification of transferred air passing through the humidification device, the humidification device is included in a mixed unit, at least one passage as a by-pass separate from said at least one passage of humidification traversing the mixed unit outside of the space occupied by said at least one humidification device, said at least one passage as a by-pass being partitioned with respect to said at least one passage of humidification and to said at least one humidification device, with the at least one passage as a by-pass being configured to direct the air transferred by the air intake unit to the dry unit without passing through the humidification device. The technical effect obtained for an air-cooling tower is to no longer be subjected to a substantial loss of pressure with regards to the obligation to pass through said at least one humidification device of the wet unit as was the case in towers according to prior art, and then even when said at least one humidification device was not in activity.

This is particularly pertinent when the air-cooling tower suit a dry operating mode, i.e. without humidification of the air which is that which is adapted to the longest period of the year, about 8 to 10 months. This dry operating mode according to prior art was accomplished by passing a flow of air in said at least one humidification device, leading to pressure losses and also a requirement to under-size the dry battery of the dry unit in order to comply with said at least one humidification device. This is no longer the case according to this invention, the dry battery able to be of dimensions greater than those of said at least one humidification device.

These losses of pressure involved substantial energy expenses and reducing them according to this invention procures ecological and acoustic advantages and reduced costs in terms of use.

The invention also relates to a method for cooling air in a hybrid air-cooling tower, with the air-cooling tower being configured to operate according to at least one wet operating mode and a dry mode, characterised in that a first flow of transferred air coming from an air intake unit passes through said at least one humidification device while a second flow of transferred air coming from the air intake unit passes through the mixed unit via the passage as a by-pass, with the flow rates of each one of the two flows able to be adjusted to the wet or dry mode.

It is as such possible to have a relatively easy adaptation to a dry or wet mode with the aforementioned advantages. This is particular true for the dry mode. The dry and wet operating modes are implemented with optimum conditions.

BRIEF DESCRIPTION OF THE FIGURES

The purposes and objects as well as the characteristics and advantages of the invention shall be understood better from the detailed description of an embodiment of the latter which is shown by the following accompanying drawings, wherein:

FIG. 1 diagrammatically shows a perspective view of a first embodiment of an air-cooling tower according to this invention with in particular a ventilation unit,

FIG. 2 diagrammatically shows a perspective top view of an embodiment of a ventilation unit that is part of an air-cooling tower according to this invention,

FIG. 3 diagrammatically shows a perspective view of the first embodiment of an air-cooling tower according to this invention, with the air-cooling tower operating according to a dry mode,

FIG. 4 diagrammatically shows a perspective top view of an embodiment of a ventilation unit that is part of an air-cooling tower according to this invention, with the air-cooling tower operating in dry mode,

FIG. 5 diagrammatically shows a perspective view of the first embodiment of an air-cooling tower according to this invention, with the air-cooling tower operating according to a wet mode,

FIG. 6 diagrammatically shows a perspective top view of an embodiment of a ventilation unit that is part of an air-cooling tower according to this invention, with the air-cooling tower operating in wet mode,

FIGS. 7 and 8 diagrammatically show a perspective view under two different viewing angles of an embodiment of a ventilation unit according to this invention provided with two compartments for freewheel.

FIG. 9 diagrammatically shows a perspective view of a second embodiment of an air-cooling tower according to this invention, with the air-cooling tower operating according to a wet mode.

FIG. 10 diagrammatically shows a perspective view of a second embodiment of an air-cooling tower according to this invention, with the air-cooling tower operating according to a dry mode.

The drawings are given by way of examples and do not limit the invention. They form block diagrams intended to facilitate the understanding of the invention and are not necessarily to the scale of the practical applications. In particular the dimensions of the various parts do not represent reality.

In what follows, reference is made to all of the figures taken in combination. When reference is made to one or more specific figures, the other figures are to be taken in combination with these specific figures for the recognition of the numerical references designated that are not present on these specific figures.

DETAILED DESCRIPTION OF THE INVENTION

Before beginning a detailed review of the embodiments of the invention, hereinafter optional characteristics are announced which can possibly be used in association or alternatively:

-   -   said at least one passage as a by-pass connects the air intake         unit to the dry unit,     -   said at least one passage of humidification opens into the dry         unit after having passed through said at least one         humidification device, the mixed unit comprising a first         enclosure integrating said at least one humidification device         and said at least one passage of humidification and a second         enclosure passed through by said at least one passage as a         by-pass that causes the air intake unit to communicate with the         dry unit. The two enclosures are hermetically sealed in order to         prevent losses of water from the first enclosure to the second         enclosure, which would have the consequence of humidifying the         dry air passing through the second enclosure, which the         invention wants precisely to avoid.     -   the first and second enclosures are separated by a wall, said         wall being in particular substantially vertical in the vertical         position of the air-cooling tower.     -   the air intake unit is a ventilation unit qui comprises at least         one freewheel drawing outside air and discharging it to the         mixed unit, said at least one passage as a by-pass being         arranged above said at least one freewheel in vertical position         of the air-cooling tower. Such a freewheel is frequently in the         form of a fan-motor assembly.     -   the ventilation unit comprises at least one freewheel drawing         outside air and discharging it to the mixed unit, said at least         one passage as a by-pass being arranged above said at least one         freewheel in the vertical position of the air-cooling tower.     -   the ventilation unit integrates inside of it the freewheel         drawing outside air and discharging the air on the same side of         the freewheel, the ventilation unit being passed through by at         least one drawing passage of outside air and by at least one         discharging passage of air opening into said at least one         passage of humidification, said at least one drawing passage and         discharging passage extending substantially parallel to one         another by being partitioned in relation to one another. The         freewheel is as such protected from inclement weather,         acoustically insulated and a gain in space is obtained. Having         the passages for drawing and for discharging on the same side of         the freewheel leaves free a side of the freewheel which can be         pressed against a wall of the ventilation unit. When the         freewheel defines a cylinder, the drawing and the discharging         are carried out on the same circular face of the cylinder.     -   said at least one passage as a by-pass communicates with the air         intake unit through at least one element for closing off, an         opening of said at least one element for closing off able to be         adjusted between at least one open position and one closed         position. The passage as a by-pass is primarily used to adapt         the circulation of air in the tower to the operating mode in         effect for the air-cooling tower, for example a dry, wet or         adiabatic mode. The closing corresponds to a wet operating mode         then in effect and the opening correspond to a dry operating         mode then in effect.     -   said at least one element for closing off can be adjusted in         intermediate positions between the opening and closing         positions. These intermediate positions make it possible to         adapt as close as possible the flow rates of dry and wet air to         the operating mode in effect. Indeed, as a wet mode can require         passing all of the air through said at least one humidification         device, a dry mode can be modulated in order to pass more or         less air through said at least one humidification device then         inactive in this dry mode.     -   said at least one element for closing off is associated with a         motor assembly for its adjustment in position. A motor assembly         allows for a very precise adjusting in position of the element         for closing off.     -   the dry unit comprises a dry battery.     -   said at least one passage as a by-pass opens through several         openings on the dry battery, at least one opening that opens         between an upper face of said at least one humidification device         of the mixed unit and a lower face of the dry battery of the dry         unit. This allows for a better distribution of the dry air         passing through the passage or passages as a by-pass over the         entire surface of the dry battery. Indeed the dry battery         comprises an expansion box, wherein the air coming indifferently         from the passage as a by-pass or from the passage of         humidification, will be distributed over all of this box         referred to as an expansion box. This expansion box makes it         possible to increase the exchange surface with the dry battery.     -   said at least one humidification device of the mixed unit         comprises, successively superimposed to the dry unit, a sprayed         battery, a spraying device and a drop separator.     -   the air intake units, wet and dry are in the form of         superimposed rectangle parallelepipeds. The units as such form         very stable blocks that can be superimposed.

For the method according to the invention, air transferred by the air intake unit passes through the mixed unit without humidification treatment in order to penetrate into the dry unit. This is very advantageous for a dry operating mode of the tower.

Advantageously, the element for closing off in an open or closed or intermediate position.

Advantageously, according to a preferred embodiment of the method in accordance with this invention, the air-cooling tower operates according to a dry mode or a wet mode, said at least one humidification device of the mixed unit being inactive in the dry mode, with, for the dry mode, between 55 and 65% of the transferred air passing through said at least one passage as a by-pass and between 35 and 45% passing through said at least one passage of humidification of the mixed unit with said at least one inactive humidification device and, for the wet mode, 100% of the air transferred passing through said at least one passage of humidification of the mixed unit with said at least one active humidification device.

Advantageously, the air-cooling tower operates according to an adiabatic mode for which 100% of the transferred air passes through said at least one passage of humidification of the mixed unit with said at least one inactive humidification device. Other intermediate operating modes are also possible.

The invention is hereinafter described in an embodiment shown in the figures, wherein three superimposed units, with a base unit allowing for a depressurising of the air at the inlet for its intake into the tower and its path, under pressure, to a mouth in the top portion of the tower. The base unit is generally an air intake unit to the rest of the tower. In the case of FIGS. 1 to 8, it contains means for pressurising incoming air, in particular in the form of means for ventilation that draw outside air. This is then a ventilation unit. In the case of FIGS. 9 and 10, the means generating the drawing are not located in the air intake unit. They are for example higher up in the tower, and in FIGS. 9 and 10 shown towards its top. At this level, one or several fans 24 can be presents in order to operate the drawing required for the circulation of air. In this case, the air intake unit is for example an air inlet orifice 25, with one or several conduits opened outwards for the taking of air, in particular grids, and channelling the flow of air towards the following unit, the mixed unit described in detail hereinafter.

By referring to all of the figures and in particular in FIG. 1, this invention relates to an air-cooling tower 1 comprising a ventilation unit 4, a mixed unit 3 and a dry unit 2, with the mixed unit 3 being superimposed on the ventilation unit 4 and the dry unit 2 being superimposed on the mixed unit 3. In FIG. 1, the air-cooling tower 1 is vertical but this tower 1 could also be horizontal, with the units 2 to 4 then able to be arranged next to one another. Generally, the units 2 to 4 are adjacent to one another.

In such an air-cooling tower 1, the ventilation unit 4 draws outside air and discharges it to the mixed unit 3, at least one passage of humidification 5 a of discharged air traverse at least one humidification device 5 of the mixed unit 3.

As can be seen in particular in FIGS. 1, 3 and 5, the dry unit 2 comprises a dry battery 14. This battery can be a battery with vanes substantially having the dimensions of the mixed unit 3.

Said at least one humidification device 5 of the mixed unit 3 can comprise successively to the dry unit 2 a sprayed battery 15, a spraying device 16 and a drop separator 17. The ventilation units 4, wet 3 and dry 2 can be in the form of rectangle parallelepipeds, advantageously superimposed.

According to the invention, at least one passage as a by-pass 6 separate from said at least one passage of humidification 5 a of said at least one humidification device 5 passes through the mixed unit 3 outside of the space occupied by said at least one humidification device 5. Said at least one passage as a by-pass 6 connects the ventilation unit 4 to the dry unit 2, said at least one passage as a by-pass 6 being partitioned with respect to said at least one passage of humidification 5 a and to said at least one humidification device 5.

The two passages 6, 5 a opening onto an expansion zone, also called expansion box. This zone is very advantageous as the air that passed preferably through a rather vertical passage was distributed better, laterally, over the entire surface constituted by the dry unit. An increased and more homogeneous transfer surface is as such obtained.

Said at least one passage of humidification 5 a can open into the dry unit 2 after having passed through said at least one humidification device 5. The mixed unit 3 can comprise a first enclosure 7 integrating said at least one humidification device 5 and said at least one passage of humidification 5 a. The mixed unit 3 can comprise a second enclosure 8 passed through by said at least one passage as a by-pass 6 having the ventilation unit 4 communicate with the dry unit 2.

There should be a partitioning of the passage or passages as a by-pass 6 with the passage or passages for humidification 5 a. In an embodiment of this invention, the first and second enclosures 7, 8 are separated by a substantially vertical wall 9 in vertical position of the air-cooling tower 1, i.e. with the units 2 to 4 superimposed. Vertical position of the air-cooling tower therefore means a position wherein the dry unit 2 is superimposed on the mixed unit 3 and the mixed unit 3 is superimposed on the ventilation unit 4.

The ventilation unit 4 can comprise at least one freewheel 10 drawing outside air and discharging it to the mixed unit 3, advantageously at variable speed. There may be several freewheels 10 each one comprising a fan-motor assembly.

The passage or passages as a by-pass 6 can be arranged above the or each freewheel 10 in vertical position of the air-cooling tower 1.

The freewheel 10 can draw outside air according to the direction of the axis of rotation of said freewheel 10 and discharge the air radially to the axis of rotation of said freewheel 10.

The ventilation unit 4 can integrate inside of it the freewheel 10 drawing outside air and discharging the air on the same side of the freewheel 10. Integrating the freewheel 10 into the ventilation unit 4 protects it and reduces the size of the tower. A basin for water removal can be located in the vicinity of the freewheel. This basin can be advantageously inclined.

The ventilation unit 4 can be passed through by at least one drawing passage 11 of outside air and by at least one discharging passage 12 of air opening into said at least one passage of humidification 5 a. Said at least one drawing passage 11 and discharging passage 12 then extend substantially parallel to one another by being partitioned in relation to one another. Said at least one discharging passage 12 of air can be configured to orient the flow of air according to at least one direction other than the direction of the axis of rotation of the associated freewheel 10.

The discharging passage 12 can be in the form of a ramp 18 oriented towards the top of the ventilation unit 4 in order to direct the discharge air to an upper portion of the ventilation unit 4. Said at least one discharging passage 12 opens into the upper portion of the ventilation unit 4 under said at least one humidification device 5 of the mixed unit 3.

The or each drawing passage 11 can have a bottom and two substantially vertical lateral partitions 20 connected by a roof 21 closing the drawing passage 11 on the upper face of the drawing passage 11, with the roof 21 able to be sloped by having two faces inclined towards a respective lateral partition 20.

In an embodiment of this invention that is particularly advantageous for the operation according to various modes of the tower, in particular but not exclusively a wet operating mode and a dry operating mode, said at least one passage as a by-pass 6 communicates with the ventilation unit 4 through at least one element for closing off 13. The opening of the element or elements for closing off 13 can be adjusted between at least one open position and one closed position.

However it is preferable that the element or elements for closing off 13 be able to be adjusted in intermediate positions between the opening and closing positions. In open position, the flows of air are balanced. In the passage 5 a, the flow of air undergoes more loads due to the device 5, consequently most of the air will pass through the passage as a by-pass 6. The or each element for closing off 13 can be associated with a motor assembly for its adjustment in position.

As can be seen in particular in FIGS. 2, 4, 6 to 8, the freewheel or freewheels 10 can be housed in a specific compartment 22 for each freewheel 10. Two compartments 22 are particularly easy to see in FIGS. 7 and 8. In these FIGS. 7 and 8, the elements for closing off have been removed and the openings 13 a that the elements for closing off can open or close are visible.

In reference to all of the figures, the passage or passages for drawing then open into the compartment 22 of their associated freewheel 10 and the passage or passages for discharging 12 leave from the compartment 22 of their associated freewheel 10. The compartment 22 of each wheel can have a ceiling pierced with openings 13 a and provided with the element or elements for closing off 13 for at least one passage as a by-pass 6 of said at least one discharging passage 12.

FIG. 3 shows an operating mode in dry mode, said at least one humidification device 5 able to be inactive in this operating mode. FIG. 5 shows a wet operating mode, no air is then passing through the passage or passages as a by-pass 6 in this mode. Another adiabatic mode is also possible.

In these figures, the arrow F1 symbolises the flow of outside air drawn in the ventilation unit 4. The arrow F2 symbolises the flow of discharged air by the freewheel 10 rotating according to the arrow Fr. The arrow F3 indicates the flow of air that has left the ventilation unit 4 through said at least one discharging passage referenced as 12 in FIG. 2 and passing through said at least one humidification device 5 of the mixed unit 3.

The arrow F4 indicates the flow of air in the passage as a by-pass 6 of the air having left the ventilation unit 4 and not passing through said at least one humidification device 5. The arrow F5 indicates the flow of air passing from the mixed unit 3 to the dry unit 2, with this air able to be the flow of air passing through said at least one humidification device 5.

The arrow F6 indicates the first flow of air that has been conveyed by the passage as a by-pass 6 of said at least one humidification device 5 and passing in the dry unit 2 and the arrow F7 indicates the second flow of air having been conveyed by the passage as a by-pass 6 of said at least one humidification device and passing in the dry unit 2, with the latter being introduced between the mixed unit 3 and the dry unit 2 so that the by-passed air is distributed over the largest surface area possible of the dry battery of the dry unit 2, with this arrow F7 being shown only in FIG. 3 only for a dry operating mode of the air-cooling tower 1. This distribution can be carried out in the aforementioned expansion zone.

As such, the air-cooling tower 1 can operate according to a dry mode or a wet mode, said at least one humidification device 5 of the mixed unit 3 being inactive in the dry mode. Without there being a limitation, for the dry mode, about 60%, advantageously from 55 to 65%, of the flow of air discharged from the ventilation unit 4 can pass through said at least one passage as a by-pass 6 and 40%, advantageously from 35 to 45% of the flow of discharged air passes through said at least one passage of humidification 5 a of the mixed unit 3 with said at least one humidification device 5 inactive in this dry mode.

This is shown in FIG. 3, with the arrows indicating the passage of the air. These percentages of about 60 and 40% can vary and be adjusted by the element or elements for closing off 13 present in the ventilation unit 4.

For a wet mode, 100% of the discharged air passes through said at least one passage of humidification 5 a of the mixed unit 3 with said at least one active humidification device 5. This is shown in FIG. 5, with the arrows indicating the passage of the air.

The air-cooling tower 1 can also operate in an adiabatic mode for which 100% of the discharged air passes through said at least one passage of humidification 5 a of the mixed unit 3 with said at least one inactive humidification device 5.

The passage or passages as a by-pass 6 and the humidification passages 5 a can open through several openings on the dry battery 14, with the flows of air in the passages as a by-pass 6 being symbolised by arrows F4 in FIG. 3, so that the wet or not wet air is properly distributed over the dry battery 14 of the dry unit 2.

For the passages as a by-pass 6, at least one opening of a passage as a by-pass 6 opens between an upper face of said at least one humidification device 5 of the mixed unit 3, therefore without passing through this humidification device 5, and a lower face of the dry battery 14 of the dry unit 2, therefore by supplying the dry battery 14 at another location than the passage or passages as a by-pass that remain, leading to a better distribution of the dry air on the dry battery 14 of the dry unit 2. This can be carried out by the aforementioned expansion zone.

The invention also relates to a method for refrigerating air in an air-cooling tower 1, with the air-cooling tower 1 being configured to operate at least according to a wet mode and a dry mode and being such as described hereinabove. In these modes, a first flow of discharged air comes from a ventilation unit 4 by passing through said at least one humidification device 5 while a second flow of discharged air comes from the ventilation unit 4 by passing through the mixed unit 3 as a by-pass of said at least one humidification device 5. The flow rate of each one of the two flows can be adjusted according to the wet or dry operating mode and said at least one humidification device 5 can be activated or not activated according to the mode chosen.

The invention is not limited to the embodiments described hereinabove and extends to all of the embodiments covered by the claims.

REFERENCES

1. Air-cooling tower

2. Dry unit

3. Mixed unit

4. Ventilation unit

5. Humidification device

5 a. Passage of humidification

6. Passage as a by-pass

7. First enclosure

8. Second enclosure

9. Wall

10. Freewheel

11. Drawing passage

12. Discharging passage

13. Element for closing off

13 a. Opening

14. Dry battery

15. Sprayed battery

16. Spraying device

17. Drop separator

18. Ramp

19. Grid

20. Lateral partition

21. Roof

22. Compartment

23. Basin

24. Fan

25. Air intake inlet

F1. Flow of drawn air

F1 a. Lateral flow of drawn air

F2. Flow of discharged air

F3. Flow of air of said at least one humidification device

F4. Flow of air as a by-pass of said at least one humidification device

F5. Flow of air between mixed unit and dry unit

F6. First flow of air from the passage as a by-pass

F7. Second flow of air of the passage as a by-pass

Fr. Direction of rotation of the freewheel 

1. Hybrid air-cooling tower comprising an air intake unit, a dry unit and at least one humidification device, the dry unit being adjacent to the humidification device, the air intake unit being configured to draw outside air and transfer it to the humidification device, at least one passage of humidification of transferred air passing through the humidification device, wherein the humidification device is included in a mixed unit, at least one passage as a by-pass separate from said at least one passage of humidification passing through the mixed unit outside of the space occupied by said at least one humidification device, said at least one passage as a by-pass being partitioned with respect to said at least one passage of humidification and to said at least one humidification device, with the at least one passage as a by-pass being configured to direct the air transferred by the air intake unit to the dry unit without passing through the humidification device.
 2. Air-cooling tower according to claim 1, wherein said at least one passage as a by-pass connects the air intake unit to the dry unit.
 3. Air-cooling tower according to claim 2, wherein said at least one passage of humidification opens into the dry unit after having passed through said at least one humidification device, with the mixed unit comprising a first enclosure integrating said at least one humidification device and said at least one passage of humidification and a second enclosure passed through by said at least one passage as a by-pass causing the air intake unit to communicate with the dry unit.
 4. Air-cooling tower according to claim 3, wherein the first and second enclosures are separated by a wall, said wall being vertical in a vertical position of the air-cooling tower.
 5. Air-cooling tower according to claim 3, wherein the air intake unit is a ventilation unit that comprises at least one freewheel drawing outside air and discharging it to the mixed unit, said at least one passage as a by-pass being arranged above said at least one freewheel in a vertical position of the air-cooling tower.
 6. Air-cooling tower according to claim 5, wherein the ventilation unit integrates inside of it the freewheel drawing outside air and discharging the air on the same side of the freewheel, with the ventilation unit being passed through by at least one drawing passage of outside air and by at least one discharging passage of air opening into said at least one passage of humidification, said at least one drawing passage and discharging passage extending substantially parallel to one another by being partitioned in relation to one another.
 7. Air-cooling tower according to claim 4, wherein said at least one passage as a by-pass communicates with the air intake unit through at least one element for closing off, an opening of said at least one element for closing off being adjusted between at least one open position and one closed position.
 8. Air-cooling tower according to claim 7, wherein said at least one element for closing off is adjustable in the intermediate positions between the opening and closing positions.
 9. Air-cooling tower according to claim 8, wherein said at least one element for closing off is associated with a motor assembly for its adjustment in position.
 10. Air-cooling tower according to claim 1, wherein the dry unit comprises a dry battery.
 11. Air-cooling tower according to claim 10, wherein said at least one passage as a by-pass opens through several openings on the dry battery, at least one opening that opens between an upper face of said at least one humidification device of the mixed unit and a lower face of the dry battery of the dry unit.
 12. Air-cooling tower according to claim 11, wherein said at least one humidification device of the mixed unit comprises a sprayed battery, a spraying device and a drop separator.
 13. Air-cooling tower according to claim 1, wherein the air intake units, wet and dry are in the form of superimposed rectangle parallelepipeds.
 14. Method for refrigerating air in a hybrid air-cooling tower according to claim 1, with the air-cooling tower being configured to operate according to at least one wet operating mode and a dry mode, wherein a first flow of transferred air coming from an air intake unit passes through said at least one humidification device while a second flow of transferred air coming from the air intake unit traverse the mixed unit through the passage as a by-pass, with the flow rates of each one of the two flows able to be adjusted according to the wet or dry mode.
 15. Method according to claim 14, wherein air transferred by the air intake unit passes through the mixed unit without humidification treatment in order to penetrate into the dry unit.
 16. Method according to claim 14 wherein said at least one passage as a by-pass connects the air intake unit to the dry unit, and wherein said at least one passage of humidification opens into the dry unit after having passed through said at least one humidification device, with the mixed unit comprising a first enclosure integrating said at least one humidification device and said at least one passage of humidification and a second enclosure passed through by said at least one passage as a by-pass causing the air intake unit to communicate with the dry unit, and wherein the first and second enclosures are separated by a wall, said wall being vertical in a vertical position of the air-cooling tower, and wherein said at least one passage as a by-pass communicates with the air intake unit through at least one element for closing off, an opening of said at least one element for closing off being adjusted between at least one open position and one closed position, and wherein the element for closing off is placed in one among of an open position, a closed position and an intermediate position.
 17. Method according to claim 15, wherein the air-cooling tower operates according to a dry mode or a wet mode, said at least one humidification device of the mixed unit being inactive in the dry mode, with, for the dry mode, between 55% and 65% of the transferred air passing through said at least one passage as a by-pass and 35 to 45% passing through said at least one passage of humidification of the mixed unit with the passage as an inactive by-pass and, for the wet mode, 100% of the transferred air passing through said at least one passage of humidification of the mixed unit with said at least one active humidification device.
 18. Method according to claim 17, wherein the air-cooling tower operates according to an adiabatic mode for which 100% of the transferred air passes through said at least one passage of humidification of the mixed unit with said at least one inactive humidification device. 